# tensorplay.functional.kaiser_window

Source: https://www.tensorplay.cn/docs/generated/tensorplay.functional.kaiser_window.html

```python
tensorplay.functional.kaiser_window(window_length, periodic=True, beta=12.0, *, dtype=None, layout=tensorplay.strided, device=None, requires_grad=False) → Tensor
```

Computes the Kaiser window with window length window_length and shape parameter beta.

Let I_0 be the zeroth order modified Bessel function of the first kind (see tensorplay.i0()) and
N = L - 1 if periodic is False and L if periodic is True,
where L is the window_length. This function computes:

$$out_i = I_0 \left( \beta \sqrt{1 - \left( {\frac{i - N/2}{N/2}} \right) ^2 } \right) / I_0( \beta )$$

Calling tensorplay.kaiser_window(L, B, periodic=True) is equivalent to calling
tensorplay.kaiser_window(L + 1, B, periodic=False)[:-1]).
The periodic argument is intended as a helpful shorthand
to produce a periodic window as input to functions like tensorplay.stft().

> **Note**
>
> If window_length is one, then the returned window is a single element tensor containing a one.

Parameters:

- window_length ([int](https://docs.python.org/3/builtins/functions.html#int)) – length of the window.

- periodic ([bool](https://docs.python.org/3/builtins/functions.html#bool), optional) – If True, returns a periodic window suitable for use in spectral analysis. If False, returns a symmetric window suitable for use in filter design.

- beta ([float](https://docs.python.org/3/builtins/functions.html#float), optional) – shape parameter for the window.

Keyword Arguments:

- dtype ([tensorplay.dtype](/docs/generated/tensorplay.DType.html#tensorplay.DType), optional) – the desired data type of returned tensor. Default: if None, uses a global default (see [tensorplay.set_default_dtype()](/docs/generated/tensorplay.set_default_dtype.html#tensorplay.set_default_dtype)).

- layout (tensorplay.layout, optional) – the desired layout of returned window tensor. Only tensorplay.strided (dense layout) is supported.

- device ([tensorplay.device](/docs/generated/tensorplay.Device.html#tensorplay.Device), optional) – the desired device of returned tensor. Default: if None, uses the current device for the default tensor type (see [tensorplay.set_default_device()](/docs/generated/tensorplay.set_default_device.html#tensorplay.set_default_device)). device will be the CPU for CPU tensor types and the current CUDA device for CUDA tensor types.

- requires_grad ([bool](https://docs.python.org/3/builtins/functions.html#bool), optional) – If autograd should record operations on the returned tensor. Default: False.